Re: [Boost-users] Threads Don't Take Turns Under Linux (Ubuntu Gutsy Gibbon)

From: Hal Vaughan (hal_at_[hidden])
Date: 2008-03-17 12:13:39

Jonathan Franklin wrote:

> On Mon, Mar 17, 2008 at 9:17 AM, Hal Vaughan <hal_at_[hidden]>
> wrote:
> 
>> So when I did just a loop in a routine that printed numbers 1-10 (or,
>> when I
>> experimented, 1-1000), and thread 1 always finished completely before
>> thread 2 could start, is that the same?  Is there any way I can get the
>> two
>> threads to run concurrently?
> 
> 
> Either give the threads more work to do (print *all* integers), or sleep
> for a second between each int.
> 
> 
>> ... I was hoping there might be a way, in C++, to spin off
>> this listener thread, let it keep listening and processing the data, and
>> have it stay in the background so other threads can continue.
> 
> 
> You can do this in C++ w/ practically any threading library.

I've tried with pthread and I have to specifically tell it to yield at some
point or the other thread doesn't get a chance to do anything until the
first thread is done.  If you have any resources that can tell me how to do
it, I'd really appreciate a few links or other info.

> 
>> So is there no way to create a thread and not have it take up all the CPU
>> time until it's done without using SMP?
> 
> 
> Throw in a periodic nanosleep (or whatever) call if the worker thread is
> doing too much work.  This will yield the processor to another thread or
> process.

That's a help.  I hadn't heard of nanosleep at all.  (Sometimes you miss a
lot when you're teaching yourself!)

Thanks!

Hal